Polyurethane foams, moldings of polystyrene resin expanded particles (hereinafter referred to also as EPS) and moldings of polypropylene resin expanded particles (hereinafter referred to also as EPP) have been hitherto utilized as shock absorbers, such as bumpers, for automobiles. EPP is superior to a polyurethane foam with respect to adaptability for recycling and lightness in weight and is superior to EPS with respect to heat resistance and solvent resistance. However, EPP has a problem because shock absorbing characteristics thereof are poor at high and low temperatures, though it exhibits good shock absorbing properties at about 20.degree. C.
JP-A-H2-158441 proposes the use of a molding of 1-butene-propylene random copolymer resin expanded particles for the purpose of improving the heat resistance of EPP. The shock absorbing efficiency of such a molding at high temperatures is, however, still fully unsatisfactory.